/*
 * Copyright 2002-2017 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.jca.support;

import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.lang.Nullable;

import javax.resource.ResourceException;
import javax.resource.spi.BootstrapContext;
import javax.resource.spi.ResourceAdapter;
import javax.resource.spi.XATerminator;
import javax.resource.spi.work.WorkManager;

/**
 * {@link org.springframework.beans.factory.FactoryBean} that bootstraps
 * the specified JCA 1.7 {@link javax.resource.spi.ResourceAdapter},
 * starting it with a local {@link javax.resource.spi.BootstrapContext}
 * and exposing it for bean references. It will also stop the ResourceAdapter
 * on context shutdown. This corresponds to 'non-managed' bootstrap in a
 * local environment, according to the JCA 1.7 specification.
 *
 * <p>This is essentially an adapter for bean-style bootstrapping of a
 * JCA ResourceAdapter, allowing the BootstrapContext or its elements
 * (such as the JCA WorkManager) to be specified through bean properties.
 *
 * @author Juergen Hoeller
 * @see #setResourceAdapter
 * @see #setBootstrapContext
 * @see #setWorkManager
 * @see javax.resource.spi.ResourceAdapter#start(javax.resource.spi.BootstrapContext)
 * @see javax.resource.spi.ResourceAdapter#stop()
 * @since 2.0.3
 */
public class ResourceAdapterFactoryBean implements FactoryBean<ResourceAdapter>, InitializingBean, DisposableBean {

    @Nullable
    private ResourceAdapter resourceAdapter;

    @Nullable
    private BootstrapContext bootstrapContext;

    @Nullable
    private WorkManager workManager;

    @Nullable
    private XATerminator xaTerminator;


    /**
     * Specify the target JCA ResourceAdapter as class, to be instantiated
     * with its default configuration.
     * <p>Alternatively, specify a pre-configured ResourceAdapter instance
     * through the "resourceAdapter" property.
     *
     * @see #setResourceAdapter
     */
    public void setResourceAdapterClass(Class<? extends ResourceAdapter> resourceAdapterClass) {
        this.resourceAdapter = BeanUtils.instantiateClass(resourceAdapterClass);
    }

    /**
     * Specify the target JCA ResourceAdapter, passed in as configured instance
     * which hasn't been started yet. This will typically happen as an
     * inner bean definition, configuring the ResourceAdapter instance
     * through its vendor-specific bean properties.
     */
    public void setResourceAdapter(ResourceAdapter resourceAdapter) {
        this.resourceAdapter = resourceAdapter;
    }

    /**
     * Specify the JCA BootstrapContext to use for starting the ResourceAdapter.
     * <p>Alternatively, you can specify the individual parts (such as the
     * JCA WorkManager) as individual references.
     *
     * @see #setWorkManager
     * @see #setXaTerminator
     */
    public void setBootstrapContext(BootstrapContext bootstrapContext) {
        this.bootstrapContext = bootstrapContext;
    }

    /**
     * Specify the JCA WorkManager to use for bootstrapping the ResourceAdapter.
     *
     * @see #setBootstrapContext
     */
    public void setWorkManager(WorkManager workManager) {
        this.workManager = workManager;
    }

    /**
     * Specify the JCA XATerminator to use for bootstrapping the ResourceAdapter.
     *
     * @see #setBootstrapContext
     */
    public void setXaTerminator(XATerminator xaTerminator) {
        this.xaTerminator = xaTerminator;
    }


    /**
     * Builds the BootstrapContext and starts the ResourceAdapter with it.
     *
     * @see javax.resource.spi.ResourceAdapter#start(javax.resource.spi.BootstrapContext)
     */
    @Override
    public void afterPropertiesSet() throws ResourceException {
        if (this.resourceAdapter == null) {
            throw new IllegalArgumentException("'resourceAdapter' or 'resourceAdapterClass' is required");
        }
        if (this.bootstrapContext == null) {
            this.bootstrapContext = new SimpleBootstrapContext(this.workManager, this.xaTerminator);
        }
        this.resourceAdapter.start(this.bootstrapContext);
    }


    @Override
    @Nullable
    public ResourceAdapter getObject() {
        return this.resourceAdapter;
    }

    @Override
    public Class<? extends ResourceAdapter> getObjectType() {
        return (this.resourceAdapter != null ? this.resourceAdapter.getClass() : ResourceAdapter.class);
    }

    @Override
    public boolean isSingleton() {
        return true;
    }


    /**
     * Stops the ResourceAdapter.
     *
     * @see javax.resource.spi.ResourceAdapter#stop()
     */
    @Override
    public void destroy() {
        if (this.resourceAdapter != null) {
            this.resourceAdapter.stop();
        }
    }

}
